The .gov means it’s official.
Federal government websites always use a .gov or .mil domain. Before sharing sensitive information online, make sure you’re on a .gov or .mil site by inspecting your browser’s address (or “location”) bar.

This site is also protected by an SSL (Secure Sockets Layer) certificate that’s been signed by the U.S. government. The https:// means all transmitted data is encrypted — in other words, any information or browsing history that you provide is transmitted securely.

Technical Abstract: Drying, by which leather acquires its final texture, consistency and flexibility, is one of the most important operations in leather manufacturing. The objective for this research is to obtain an improved drying method, merging toggling and vacuum drying together. This is because vacuum drying offers fast speed and low temperature drying, which is particularly advantageous to heat-vulnerable chrome-free leathers. Adding a toggle action, such as stretching during vacuum drying, can potentially increase the area yield. We explored this composite drying method and investigated how drying variables affect the drying rate and mechanical properties of chrome-free leather that was tanned with glutaraldehyde. Using a statistical experimental design, a second order polynomial equation was derived to quantitatively describe the relationship between the drying rate and three major independent variables: drying temperature, stretch %, and drying time. Drying rate models derived from this investigation provide a clear understanding of the drying process for chrome-free leather. The drying constant indicates that chrome free leather dries faster than chrome-tanned leather. These models will help the leather industry estimate the right drying parameters to dry leather. Our studies showed that stretch % during vacuum drying is the most significant variable affecting the stiffness and area retention of leather. This research indicated that stretching should not be overdone and the preferable length increase should not be greater than 10%; otherwise poor leather properties may result, such as an elongation less than 40% and toughness index less than 1.